NEURO: VALPROATE

Question 1

VALPROATE: INDICATIONS

Answer 1

• Epilepsy

- Bipolar Disorder

Question 2

VALPROATE: MOA

Answer 2

• Weak inhibitor of neuronal sodium channels

- Increases the brain content of y-aminobutyric acid (GABA), principle inhibitory NT = regulating neuronal excitability

Question 3

VALPROATE: ADVERSE EFFECTS

Answer 3

• GI upset
• Neurological and psychiatric symptoms
• Thrombocytopenia
• Transient increase in liver enzymes
• Hair loss -> subsequent regrowth curlier than normal hair
• RARE => life threatening idiosyncratic adverse effects (severe liver injury, pancreatitis, bone marrow failure and anti epileptic hypersensitivity syndrome)

Question 4

VALPROATE: WARNINGS

Answer 4

• Women of child bearing age
• Conception
• First trimester of pregnancy
• Greatest risk of fetal abnormalities = neural tube defects, craniofacial, cardiac and limb abnormalities and developmental delay
• Hepatic and renal impairment patients

Question 5

VALPROATE: INTERACTIONS

Answer 5

• Drugs metabolised by Cytochrome p450 enzymes (warfarin and anti epileptic drugs)
• Risk of seizures increased in cytochrome p450 inducers (phenytoin and carbamazepine)
• Increased adverse effects with cytochrome p450 inhibitors = macroclides and protease inhibitors
• Efficacy of antiepileptic drugs = drugs that lower the seizure threshold (SSRIs, TCAs, antipsychotics and tramadol)

Question 6

VALPROATE: EXAMPLES

Answer 6

• Sodium valproate

- Valproic acid